Brood lord

"I’m happy to announce that lastly, we have learned the details on the most terrifying of all Zerg forces: the Brood Lord. A true monster of the sky, the Brood Lord can unleash utter devastation upon any foes on the ground."

The brood lord was originally morphed from the corruptor.[1] The glowing bulbs on the brood lord's back are an evolution of the cancerous growths in the corruptor's tentacles. Alterations at the genetic level turned the growths into sacs capable of rapidly spawning large batches of broodlings. Its tail is also derived from the corruptor, namely its statocyst. The brood lord's tail structure (including the spikes) constitutes a large biological gyroscope that maintains the creature's level and orientation. The tail is directly linked to the brood lord's sensory organs, increasing its capability to locate prey. Bone spikes located on the frontal section of the brood lord's wings house an advanced glandular system capable of emitting and receiving high-frequency electrical pulses. With each pulse, a massive spherical field radiates from the creature, coating its surroundings and targets in bio-electric energy. Afterwards, the brood lord's acute receptor glands pick up and process the gathered data. During deep space flights, the glands mutate to detect sources of radiation, electromagnetism, and light.[2] In battle, if the Swarm gains air/space superiority, it is common for them to evolve their fleet of corruptors into brood lords en masse to help with the ground battle.[3]

An aquatic brood lord

Brood lords are also capable of adapting their biology to suit their theater of combat. During the invasion of a planet with exceptionally large seas, brood lords evolved to be more suited in aquatic combat, allowing them to chase their prey deep into the planet's trenches. Leviathan Brood brood lords retain the brood's pre-disposition for spikes, possibly as a result of Abathur's experimentation.[4]

The brood lord releases biological symbiotes on ground targets. These small creatures regulate some of the brood lord's biological functions, and can also serve as living ammunition. The brood lord has clusters of broodlings squirming under its carapace at any given time. In combat, the brood lord supercharges the broodlings’ aggression and metabolism, turning them into short-lived—but very effective—air-to-ground weapons.[2] Each broodling starts out as a projectile, inflicting initial impact damage. But once on the ground, they enter a frenzied melee assault,[3] tearing through personal armor and vehicular plating with ease[2] until they reach the end of their short lifespan or are destroyed. Left unmolested, a brood lord will disgorge a steady stream of broodlings capable of ravaging even large armored units in quick succession.[3] However, brood lords themselves are not very durable, and are vulnerable against aerial-strike combatants.[1]

Brood lords replace guardians as the zerg aerial bomber. Like the guardian, it has a long-ranged ground attack and no defense against air units. Brood lords launch broodlings; the broodlings do damage upon impact, and then act as separate timed-lifespan ground units. Brood lords can sustain a stream of single broodlings; the first attack after a break launches two broodlings. Unless the enemy uses extensive micro-management or air-to-air fighters, the broodlings are an excellent distraction for ground-to-air units on top of the damage boost. Left unchecked a relatively small group of brood lords can end up doing catastrophic damage to an enemy base since very few enemy units or turrets will end up actually firing on them.

Compared directly to other "siege" units the brood lord is a powerful late game option. Like other siege units it can out-range defense turrets, but it's ability to fly gives it several advantages over the others. For one, most of the other siege/anti ground units can't even fire on it. Flight also gives it even better mobility than immortals by letting it pass clean over truly impassible terrain, such as lava lakes and deep canyons, letting them attack enemy bases from usually unexpected directions. A group of brood lords supported by anti-air units such as corruptors or even baseline mutalisks can be very difficult to stop.

However, brood lords on their own are slow and immobile, and are vulnerable to attacks from vikings and phoenixes. If anti air units such as stalkers are able to get under them and focus fire, they can be brought down with relative ease. Their high cost and high place on the tech tree also makes it hard to amass a critical number of brood lords without also investing in other units to defend from harassment and timing pushes in PvP.

In the Heart of the Swarm campaign, the brood lord is one of the evolution choices for the mutalisk. Choosing the brood lord prevents the use of the viper.[5] The Viper is akin to a Corsair, purely anti-air barely more capable than a mutated Mutalisk with some ground disruption and the ability to move ground units to itself, but this is still barely helpful in comparison to a swarm of Brood Lords that can easily level entire bases over time, including ones that the campaign commanders say "Don't attack there it's too well defended".

The following section contains information from a previous version of StarCraft II which is no longer valid.

During the development of StarCraft II, it replaced the swarm guardian.[7] At some point it possessed the name Mantalisk.[8]

The combat role of the brood lord fluctuated for a very long time. Many variations of the guardian were presented but the intention was always clear that the development team wanted more out of this new flyer. Finally out of the blue, Samwise Didier concepted the brood lord like a bolt of lightning and thus the design team created the 3D art in accordance to his concept. The head design was lifted from the scrapped morphalisk.[9]